Cervical Screening Programme, England - 2020-21 [NS]

Those who have a negative HPV test result are returned to routine screening and no further tests are carried out on the sample.

Those who have a HPV positive screen with a cytology negative result, will be recalled in 12 months for a further screen. If the 12 month screen is also HPV positive and cytology negative then they are recalled after a further 12 months when an HPV positive test with any cytology result will cause a referral to colposcopy.

Those who have an HPV positive screen with an abnormal cytology result are referred to colposcopy. Those with 2 consecutive HPV unavailable or cytology inadequate screening tests in any combination will be referred to colposcopy.

For further details see the quality statement.

HPV primary screening was fully  implemented in December 2019, following a pilot that was launched in 2013.

This replaced HPV triage screening, where samples were first examined under a microscope for signs of cytological abnormality. Where a test result showed borderline change or low-grade dyskaryosis (abnormal cell changes), the sample was then tested for infection with high-risk HPV (Human Papillomavirus).

An inadequate sample result can be assigned following a test outcome of either HPV unavailable or cytology inadequate.

Individuals who have an inadequate sample are either tested again or referred to colposcopy.

Colposcopy referrals are made following either:

• 2 consecutive HPV unavailable or cytology inadequate screening tests in any combination (under HPV primary screening).

The proportion of inadequate samples has fallen since the introduction of Liquid Based Cytology (LBC) in 2004-05.

In 2020-21, 0.4% of all samples were inadequate, a decrease from 1.2% in 2019-20 and 2.3% in 2018-19.

The reduction in inadequate samples in 2020-21 is thought be related to the implementation of HPV primary screening. Under HPV primary screening, a HPV negative result means cytology is not required. Therefore, cytology tests, which have a higher rate of inadequate results, are used less often.

The proportion of inadequate samples decreased in all age groups compared to the previous year.

 The chart below shows that the proportion of inadequate samples reduced in all age bands in 2020-21 compared to 2019-20.
 

In 2020-21, individuals aged 25 to 64, all 8 laboratories had inadequate sample rates of less than 1.0%. There is data for 45 laboratories in 2019-20.

In 2020-21, for individuals aged 25 to 64:

• 95.6% of samples were reported as being negative.
• 2.2% of tests were reported as low-grade dyskaryosis.
• 1.2% of tests were found to have borderline changes.
• Those below the age of 30 were amongst those most likely to have an abnormal test result (see data table 15).

* ?invasive carcinoma means ‘suspected invasive carcinoma’, ?glandular neoplasia (endocervical) means ‘suspected glandular neoplasia of endocervical type’
NB. The sum of components may not equal totals due to rounding.
Source: KC61, NHS Digital. See data table 15.

The percentage of laboratory tests authorised (test confirmed) within 2 weeks rose to 86.7% in  2020-21, an increase from 61.7% in 2019-20.

Prior to 2016-17 the percentage authorised within 2 weeks had been above 90% since 2010-11.

The increase in time to authorisation of reports in recent years is attributable to the time taken to implement HPV primary screening. This affected capacity in laboratories due to reduced workforce. Further details can be found in Appendix J.

Regional versions of the chart above are available in the interactive report accompanying this publication.

There are 2 main colposcopy referral groups

Standards

The distribution of individual laboratory results is used by the programme for quality assurance purposes in monitoring performance.
Where laboratories fall outside specified ranges (standards) there is a requirement to investigate the reason(s) for this.

The standards that laboratories are required to adhere to are outlined in cervical screening programme standards.

There are 3 key values used for assessing laboratories which are summarised below with further details available in Appendix B. Values should be considered alongside other information rather than in isolation.

For standards, when a laboratory is outside the 5th to 95th percentile range (see table below) this may require further investigation.

The 5th to 95th range for RV is also provided in the table below. Although no longer a standard, RV is still used by the programme for quality assurance purposes.

* The percentile ranges for the PPV, RV and APV indicators are calculated using data from the previous year (KC61, Part C2). For example, the PPV for 2020-21 is based on data from 2019-20.
See Appendix B for definitions of PPV, RV and APV and see Appendix E on Outcomes of Gynaecological Referrals for further information about cervical intra-epithelial neoplasia (CIN).
NB: Individuals with negative cytology but who test positive for HPV and are referred to colposcopy are not currently included in the calculation of referral value. See Appendix B – Definitions for more information.
Source: KC61, NHS Digital. See Data Tables 19 and 19a

Inadequate samples

** Based on results for individuals aged 25 to 64 tested in GP and NHS community clinics only.

For 2020-21, the full range of values is shown as there is only data for 8 laboratories.

Source: KC61, NHS Digital. See Data Tables 19 and 19a